I use the "Merge to 32-Bit" Plugin with the photomatix software to do my HDR editing. With the new update from Adobe, this plugin has stopped working. Does anyone know if this is because Adobe LR has blocked it or something along those lines or is this just a glitch in the new update?

Thanks dj_paige, and I already have sent an email to their tech support still waiting on a response from them. However, the plugin worked just fine before the update and now it has stopped working so my first guess would be this is a LR issue. But I'll take an answer that gets it working from anybody!

Same exact issue here; haven't see much discussion of this online, but the CC LR update (2015.4) is very recent. I tried deleting and re-adding the plug-in also (Photomatix 5.1.1), with no luck. Mac 10.11.3 El Capitan.

Since I upgraded Lightroom to version 6.4, nothing happens after exporting to Photomatix Pro

Lightroom CC 2015.4 / 6.4 introduces a bug that makes the Plugin fail to export to Photomatix Pro on Mac OS X.Our engineers have implemented a workaround that fixes the issue. The fix updates the Photomatix.lrplugin file to version 5.1.1a.

Photomatix has gotten back to me once again, and this time with a link that fixes all photomatix plugins in LR. I have already tested it and all the plugins included the merge to 32 bit are working again. Thanks to the photomatix team!